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Updated: May 3, 2026
08:37
Forming, Confining, and Observing Microtubule-Based Active Nematics
Published on: January 13, 2023
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Pseudo-Casimir interactions across nematic films with disordered anchoring axis
Fahimeh Karimi Pour Haddadan1, Ali Naji, Azin Khame Seifi
1Faculty of Physics, Kharazmi University, Karaj 31979-37551, Iran.
Summary
We investigated how random anchoring on a surface affects forces between liquid crystal films. Disorder effects dominate at intermediate distances for quenched disorder but are negligible for annealed disorder.
Area of Science:
- Soft Matter Physics
- Materials Science
- Condensed Matter Physics
Background:
- Liquid crystal films exhibit unique interfacial properties.
- Surface disorder can significantly alter bulk material behavior.
- Casimir forces are crucial in understanding interactions at small scales.
Purpose of the Study:
- To investigate the impact of surface disorder on pseudo-Casimir forces in nematic liquid crystal films.
- To differentiate the effects of quenched versus annealed disorder on inter-surface interactions.
- To analyze fluctuation-induced forces mediated by disordered liquid crystal interfaces.
Main Methods:
- Theoretical analysis of effective pseudo-Casimir interactions.
- Modeling of nematic liquid-crystalline films with disordered anchoring.
- Consideration of both quenched and annealed disorder scenarios.
- Analysis of interaction forces at varying inter-surface separations.
Main Results:
- For quenched disorder, effects are additive and dominant at intermediate separations.
- Disorder effects become unimportant at very small and very large separations.
- For annealed disorder, effects are non-additive and can be described by renormalized extrapolation length.
Conclusions:
- Surface disorder plays a critical role in modulating inter-surface forces in liquid crystals.
- The nature of disorder (quenched vs. annealed) dictates its impact on interaction strength and range.
- Understanding these effects is vital for designing novel liquid crystal-based devices and materials.
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